docs: def _load_sequences_to_strain(self, strain_id, force_rerun=False):
          """Load strain GEMPRO with functional genes defined, load sequences to it, save as new GEMPRO"""
          gp_seqs_path = op.join(self.model_dir, '{}_gp_withseqs.pckl'.format(strain_id))
  
          if ssbio.utils.force_rerun(flag=force_rerun, outfile=gp_seqs_path):
              gp_noseqs = ssbio.io.load_pickle(self.strain_infodict[strain_id]['gp_noseqs_path'])
              strain_sequences = SeqIO.index(self.strain_infodict[strain_id]['genome_path'], 'fasta')
              for strain_gene in gp_noseqs.functional_genes:
                  # Pull the gene ID of the strain from the orthology matrix
                  strain_gene_key = self.df_orthology_matrix.at[strain_gene.id, strain_id]
                  # Load into the strain GEM-PRO
                  new_id = '{}_{}'.format(strain_gene.id, strain_id)
                  if strain_gene.protein.sequences.has_id(new_id):
                      continue
                  strain_gene.protein.load_manual_sequence(seq=strain_sequences[strain_gene_key], ident=new_id,
                                                           set_as_representative=True)
              gp_noseqs.save_pickle(outfile=gp_seqs_path)
  
          return strain_id, gp_seqs_path